The subject matter disclosed herein relates to the art of turbomachines and, more particularly, to a cross-over purge flow system for a turbomachine wheel member.
Gas turbomachines include internal and rotating, components that may be subjected to high temperatures. In a compressor, rotor components are subjected to high temperatures and temperature gradients that lead to low cycle fatigue, embrittlement, and creep, all of which have a detrimental effect on system performance and durability. In order to enhance system performance and extend component life, turbomachines include purge systems that direct cooling air flows onto various components. Existing purge systems rely on a single stage pressure drop to drive air flow around wheel surfaces. A purge air flow starts at a region of higher pressure in the flowpath, travels inward toward a wheel bore region, and back to a region of lower pressure in the flowpath. In this manner, the purge air flow reduces temperature gradients as well as lowers peak rotor wheel temperature to enhance component life and turbomachine operability.